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Fusion scientists of the future

In interdisciplinary subjects such as fusion energy, training PhD students is a complex task. Llion Marc Evans describes how being part of the Fusion Doctoral Training Network has helped him develop as a researcher.

Courtesy: University of Manchester

Critics of UK physics education often argue that PhD programmes at many universities are both too short and too narrow in focus. In recent years, the Engineering and Physical Sciences Research Council (EPSRC) has responded to such criticisms by introducing doctoral training centres (DTCs) in several different fields, from energy research to the life sciences, at universities across the country. These are designed to produce PhD students who are better equipped to do their own research in their later careers – partly by adding an initial period of formal training to the traditional three-year research PhD, but also by bringing together researchers from a particular subject or geographic area to create regional "centres of excellence".

One such scheme is the Fusion Doctoral Training Network (FDTN). This collaboration between the universities of Durham, Liverpool, Manchester and York aims to bring together students from different fusion-relevant disciplines – including physics, engineering and materials science – to give them a better picture of the subject as a whole and to help them work towards a common goal. As part of the scheme, students spend six months at the University of York taking lecture courses in subjects such as plasma physics and fusion technology, and learning skills such as computer programming and statistical methods. This is followed by a three-year PhD research programme at the students' home universities or the network's industrial partners, which include the Rutherford Appleton Laboratory and the Culham Centre for Fusion Energy (CCFE) in Oxfordshire

The FDTN is quite a new initiative – its first class of eight students joined in October 2009 – so it is still too early to evaluate how successful it has been. However, my experience as one of those eight students makes me think that this template is worth replicating in other departments and fields of research. Indeed, this is already happening to some extent: in 2009 EPSRC funded 50 new DTCs across the UK.

From Formula 1 to fusionMy educational background is a good example of the different ingredients that make up fusion science. After obtaining an undergraduate degree in physics at the University of Wales, Aberystwyth, I went on to do an MSc in computational fluid dynamics at Imperial College London. My Master's thesis involved working with researchers in the Formula 1 department at Ferrari, who were interested in modelling heat transport in brake disks. Shortly after I finished the MSc, I went for preliminary interviews at Ferrari's headquarters in Maranello, Italy, and seemed to be on track for a career in F1 racing.

At that time, however, media attention was increasingly focusing on the world's carbon emissions and a looming energy crisis. Keen to find a solution to these environmental problems, I began weighing up my future career options, and found myself drawn away from F1 towards a PhD in fusion energy.

After decades of research, the underlying theory behind fusion is relatively well established. The emphasis of current research is on the practicalities of designing a power plant that can deliver commercially viable energy in a safe and environmentally responsible way. Having completed a BSc in physics and an MSc in engineering, I felt that this field would allow me to combine the theoretical know-how of physics with the pragmatic, problem-solving approach of engineering.

The project I am working on now at the University of Manchester uses a technique called image-based modelling to predict how components will behave in a fusion-power-plant environment. We begin by taking a computerized tomography (CT) scan of a sample component, which lets us build a computational model that includes cracks, holes and other features present in the sample that are introduced in the manufacturing process and would not be included in models that use an idealized geometry. This leads to more accurate results in simulating material behaviour. In addition, because it is possible to carry out tests using identical samples, direct comparisons can be made between experimental and computational results.

An interdisciplinary approachOf course, not everyone in the 2009 group of FDTN students at York was interested in this type of research project. The biggest challenge to those designing the course was to cover topics that would be relevant to everyone, despite our diverse research interests in plasma physics, materials science, neutronics, and electronic engineering and diagnostics. The course designers also had to make sure that they included material that was relevant to both magnetic and inertial-confinement fusion, which use strong magnetic fields and powerful lasers (respectively) to produce the conditions necessary for fusion.

Most researchers in the University of York's fusion group are interested in plasma physics, so other topics, such as high-performance computing, were covered by bringing in lecturers from outside the plasma-research groups. The programme also invited guest lecturers for week-long courses such as "fusion technology" and a "frontiers of fusion" conference. This year's intake of students will benefit from a similar course on the materials used in fusion, which we are also welcome to attend.

For me, the benefits of this training period started right away. During my first week of research, I had to present a talk on the fusion-energy industry and my research plans at a conference on nuclear technology. Thanks to the broad education I received, I felt comfortable answering questions far beyond my own research topic. This is not something I would have got from a "traditional" PhD programme, which does not include the kind of training period I went through as part of the FDTN.

Another positive effect has been the sense of community that the programme has created among PhD students from different disciplines and universities. As we develop our careers in the fusion-energy sector, I believe my former classmates and I will continue to benefit from this informal network and the way it helps us to see the wider picture. It may be premature to make too much of this aspect after just one year, but so far, despite being spread over various locations, the eight of us are still in regular contact – collaborating on research, representing fusion energy at conferences and participating in school outreach programmes.

As the number of FDTN students grows, so will the community. In October last year, 10 new students began their period of formal study at York, and during their first week we joined them for a "team building" day. This was the first of several events planned for the coming year that will help all of us who end up working in the field.

A final advantage of the FDTN comes from the scheme's close links to industrial partners. These links give us unprecedented access to the expertise and knowledge of those already working in industry. Students who, like me, want to continue their careers in that direction will also benefit from first-hand experience of the working environment at facilities such as the CCFE.

The bottom line is that this training scheme has been designed not just to produce postgraduate students, but to develop future researchers for the fusion-energy industry. With the world's largest fusion tokamak, ITER, currently under construction in southern France (and the world's largest laser, at the National Ignition Facility, already performing pre-fusion experiments in northern California), this type of investment is crucial to the future of the field. Funding for facilities is wonderful, but without skilled workers to operate them, fusion-energy research will grind to a halt.

About the AuthorLlion Marc Evans is a PhD student at the University of Manchester, UK, e-mail llion.evans@postgrad.manchester.ac.uk.

This article originally appeared in the January 2011 issue of Physics World.